This is a proposal to build upon the activities of an existing CDC Public Health Informatics Center of Excellence to support public health practice to prevent chronic diseases and their sequelae. Diabetes, one of the country's five major chronic diseases, will serve as the use case for establishing advanced disease surveillance, analysis, and reporting capability. This partnership between academic health centers, urban and rural delivery systems caring for diverse and underserved populations, and a state department of public health will build upon its experience in infectious disease surveillance to develop a chronic disease surveillance platform centered on a generalizable, open-source, grid-enabled information system to routinely extract and analyze population-level diabetes summary information from 1) the electronic medical record systems of a diverse set of medical practices and 2) personally controlled health records linked to social network systems. We will present this information to different classes of public health users, providers, and individuals in ways that best support their needs. Each of our two core projects addresses this program project's five aims: 1) Create new electronic data based, measures of diabetes epidemiology, care, and outcomes;2) develop grid-enabled methods to support bi-directional communication of health information;3) create the RiskScape, a customizable user interface to guide public health practice;4) evaluate improvement in the quality, completeness, and timeliness of data that can support public health practice;5) disseminate our findings and products through publications, open source release, documentation and promotion of results.